Reaction Steps
The title compound was prepared in 44% yield from methyl 4-((1R,3aS,5aR,5bR,7aR,11aS,11bR,13aR,13bR)-3a-amino-5a,5b,8,8,11a-pentamethyl-1-(prop-1-en-2-yl)-2,3,3a,4,5,5a,5b,6,7,7a,8,11,11a,11b,12,13,13a,13b-octadecahydro-1H-cyclopenta[a]chrysen-9-yl)benzoate following the same procedure as described for the preparation of 4-((1R,3aS,5aR,5bR,7aR,11aS,11bR,13aR,13bR)-3a-(3-(dimethylamino)propanamido)-5a,5b,8,8,11a-pentamethyl-1-(prop-1-en-2-yl)-2,3,3a,4,5,5a,5b,6,7,7a,8,11,11a,11b,12,13,13a,13b-octadecahydro-1H-cyclopenta[a]chrysen-9-yl)benzoic acid, except 2-thiomorpholinoacetic acid was used instead of 3-(dimethylamino)propionic acid hydrochloride in Step 1. LCMS: m/e 671.8 (M−H)−, 2.37 min (method 6). 1H NMR (500 MHz, 1:1 CDCl3:MeOD) δ=7.92 (d, J=8.2 Hz, 2H), 7.47 (s, 1H), 7.20 (d, J=8.2 Hz, 2H), 5.29 (d, J=4.3 Hz, 1H), 4.75 (s, 1H), 3.79-3.63 (m, 2H), 3.58 (td, J=6.5, 12.9 Hz, 1H), 3.47-3.35 (m, 3H), 2.95 (br. s., 4H), 2.68-2.57 (m, 2H), 2.37 (dd, J=8.4, 12.4 Hz, 1H), 2.13 (dd, J=6.4, 17.1 Hz, 1H), 1.92-1.82 (m, 2H), 1.81-1.76 (m, 1H), 1.73 (br. s., 1H), 1.71 (s, 3H), 1.69-1.64 (m, 1H), 1.60-1.31 (m, 12H), 1.30-1.22 (m, 1H), 1.19-1.11 (m, 2H), 1.09 (s, 3H), 1.03 (s, 3H), 1.01 (s, 3H), 0.94 (br. s., 3H), 0.93 (br. s., 3H).
